Himmler was captured on May 21, 1945, as he fled the republic in disgrace for attempting to broker a peace settlement behind Hitler’s back.

Mr Mannion’s grandfather L/Sgt Patrick Mannion of Newton le Willows, Mersyside, was one of five men in the patrol which arrested him.

He said he was ‘absolutely stunned’ when he discovered his grandfather was one of those involved in the capture of one of the most wanted men in history, and now wants to find the identity of others involved.

He has identified two of the soldiers, and believes one of the five Sheffield men could be part of the remaining pair.

Mr Mannion, a volunteer at the Imperial War Museum in Salford, said: “I know all these Sheffield men were members of the 196 battery.

“They used these addresses when they signed up. Some of the addresses no longer exist. I know they were not killed, but little else. So were they one of the other men? Are they in the battery photo above?

“I am trying to find any living relatives to see if they have any information, photographs, stories, service records.”

Mr Mannion is also keen to speak with the relatives of L/Bdr D R Parker of Bridport Road, Attercliffe, Sheffield, who was killed in action.

n Anyone with information can contact Mr Mannion by email on antitank73@hotmail.com